lm386 heatsinks

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The LM386 is not a good choice for bridging. Current drive is so limited with it that power folds up quite a bit under load.

Here's a list of IC output power using a regulated 9v supply. The power is continuous sine wave before clipping into non inductive loads.
An externally hosted image should be here but it was not working when we last tested it.

As you can see, some ICs can practically double the output of the LM386 with 4 ohm loads.
 
The LM386 is not a good choice for bridging. Current drive is so limited with it that power folds up quite a bit under load.

Here's a list of IC output power using a regulated 9v supply. The power is continuous sine wave before clipping into non inductive loads.
An externally hosted image should be here but it was not working when we last tested it.

As you can see, some ICs can practically double the output of the LM386 with 4 ohm loads.

thanks :D in the end its just an expiriment lol but that table helps
 
Let me add the Chipamp I use commercially: TBA820M .
I searched a lot and it's the best one available when the supply is 9V.
And it keeps working down to 3V, so *very* dead batteries still provide *some* sound to save a boring night, until shops open in the morning.
From its datasheet:
Output power: Po = 2W at 12V/8r , 1.6W at 9V/4r
and 1.2W at 9V/8r.
www.kolumbus.fi/mikko.esala/d/tba820.pdf
Can be bridged for incredible 3.2W RMS into 8r out of a 9V supply.
 
I downloaded the tba820 datasheet, thinking it would be useful.
Now that I have read said datasheet, I have not saved it. The performance is dreadful.
minimum distortion ~1/3 of a percent.
0.5% distortion at 1/2W
noise -70dB ref 1.2W

I wonder if it is a ClassB output stage to save battery power?
 
I downloaded the tba820 datasheet, thinking it would be useful.
Now that I have read said datasheet, I have not saved it. The performance is dreadful.
minimum distortion ~1/3 of a percent.
0.5% distortion at 1/2W
noise -70dB ref 1.2W

I wonder if it is a ClassB output stage to save battery power?

This is an ancient chip. It needs a lot of external components to make it work including external frequency compensation (not common on modern low power audio amp ICs). Distortion isn't really that bad. I doubt it could swing any better than 2.25 Vrms into an 8 ohm load @ 9v Vs. Some tube nuts would say a 35C5 SE tube amp, with a few percent distortion at best, would sound better.
 
¿Dreadful?? 1/3 of 1% ??? -70dB noise??? :confused:
Get REAL folks, it's a chip designed for 9V battery portable stuff. :rolleyes:

Leave cork sniffing to those guys who can justify it.
As in 30Kg PSU Class A with no feedback and such.

Yes, it has exactly 4 (four) extra components, compared to, say, an LM1875 or TDA20xx , those being:
1 and 2 ) a bootstraped resistor and capacitor , which by design swing *beyond* the 9V rail for full drive.
A more "modern" and linear Constant Current source, from a PNP transistor hanging from said rail, will *lose* the CE saturation voltage, and in *no way* will swing above it.
3) an external compensation capacitor, which is *good* because it lets you get stability at widely different closed loop gains, while many chipamps can not go below, say, 15dB because they start oscillating.:eek:
4) an (optional) ripple compensation capacitor, for those who want to increase ripple rejection. At least now you have the option. ;)

Precisely that's the point: to use efficiently up to the last tenth of a volt (which is the precious commodity here), they added some external bootstrapping ... big deal.:D

But of course, it's the end user decision.
If he prefers to lose 25% power to lower distortion from 0.3% to 0.003% , that's his choice.
In any case, what I see is that when my TBA820 starts clipping, "the others" are supplying a nice squarewave struggling to reach same power. ;)
And then, how much distortion we have?
Just sayin' :hohoho:

Of course, anybody can use whatever he wants.
Including paper in oil caps, silver wire wound transformers, cryogenically treated tubes and wool from Woolly mammoths cabinet damping.
Why not?
 
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